Nutrients: How Much Do You Need?
One question I occasionally get is how much of a given nutrient a patient needs or should have. The answer is “it depends”. It depends on the person’s goal. There are three categories of nutritional status with regards to the amounts of nutrients needed. We could consider these levels philosophical approaches to nutrition.
- Amounts needed to survive.
- Amounts needed for optimal health.
- Amounts needed maximum performance.
Unfortunately in the practice of medicine we tend to limit our nutritional approach to the amounts for survival – the bare minimum. That’s really what the RDAs (Recommend Dietary Allowances) are about – survival. That’s a pretty sad goal and RDAs are an antiquated approach to nutrition. RDAs do not cover individuals with special nutrition needs (athletes, pregnant women, ill elderly, etc).
RDAs represent the minimum amounts of nutrients needed to prevent a nutritional deficiency, which is far different than the amount for good health.
In fact, the term “RDA” is rarely used today and has been replaced by the term RDIs (reference daily intake). You will also see Daily Values (DVs) on today’s food labels, and DRVs (daily reference values for fat, saturated fat, cholesterol, protein, fiber, sodium, and potassium).
Most patients, though, want to do more than survive – at the very least they would like nutritional levels for optimal health. And, that is where the focus needs to be re-directed in medicine – to levels to achieve optimal health.
Nutrition for Optimal Health
A better guide to use than the RDAs if your goal is optimal health is the Optimum Daily Allowance, or ODA. The ODAs are not government recommendations. The ODAs provide extra amounts of nutrients that enable us to better deal with air pollution, contaminated water, additives, pesticides, and stress of any type. They geared to the amounts of nutrients needed to achieve optimal health, not just the amounts to avoid disease.
If you look at this table that compares the RDAs to SODA (suggested optimal daily allowance) you will see a huge difference between the recommendations for some nutrients – sometimes two to three times the RDAs.
Nutrition for Maximum Performance
Athletes have even higher nutritional needs that go beyond optimal health. Nutrients are lost in sweat, and additional nutrients are needed to repair muscle and in general, facilitate post-exercise recovery. Athletes focus on performance and their nutrition plans are designed to make availabe various energy sources depending on athlete’s sport or event.
Some organizations like the International Sports Sciences Association (ISSA) talk about the importance of using Performance Daily Intakes or PDIs for atheltes. PDIs take into account andathlete’s size and sport or event. They include nutrients not seen in the RDAs, RDIs, and ODAs. PDIs are more individual specific.
Sources of Nutrients
Ideally, nutrients should be obtained from food sources, but in the case of athletes to achieve PDIs many times means using supplements. Otherwise, an athlete would need to take in an overabundance of calories to meet their nutritional needs. In other words, supplements provide nutrients without providing more calories than necessary.
Most of us would benefit from use of ODAs, and if you’re extremely physically active you would be wise to meet with a sports nutritionist to determine your Performance Daily Intakes.